Implementing change data capture by interpreting published events as a database recovery log

ABSTRACT

A method for implementing a change capture system using an event publishing system as a database recovery log is provided. The method may include determining a set of data based on a description of events for which change capture is possible. The method may also include selecting at least one item of data from within the determined set of data, wherein the at least one item of data requires change capture to be performed. Additionally, the method may include identifying at least one published event, wherein the at least one published event is produced by the event publishing system. The method may include instructing the event publishing system to deliver the at least one identified published event to the change capture system. Furthermore, the method may include receiving the at least one identified published event. The method may also include processing the at least one published event.

BACKGROUND

The present invention generally relates to the field of computing, andmore particularly to the capturing of data changes.

Change capture (e.g. change data capture) technology utilizes thedatabase recovery log from the source database to determine the changesthat occur in the database. This has impact, both in resources and inadministration, for the source database and the system on which itresides. Change capture solutions may encompass a variety of use casesthat may include homogeneous replication, heterogeneous replication, andevent publishing.

SUMMARY

A method for implementing a change capture system using an eventpublishing system as a database recovery log is provided. The method mayinclude determining a set of data based on a description of events,wherein the set of data comprises a plurality of data for which changecapture is possible. The method may also include selecting at least oneitem of data from within the determined set of data, wherein the atleast one item of data requires change capture to be performed.Additionally, the method may include identifying at least one publishedevent based on the at least one selected item of data, wherein the atleast one published event is produced by the event publishing system.The method may include instructing the event publishing system todeliver the at least one identified published event to the changecapture system. Furthermore, the method may include receiving, by thechange capture system, the at least one identified published event. Themethod may also include processing the at least one published eventreceived by the change capture system.

According to another embodiment, a computer system for implementing achange capture system using an event publishing system as a databaserecovery log is provided. The computer system may include one or moreprocessors, one or more computer-readable memories, one or morecomputer-readable tangible storage medium, and program instructionsstored on at least one of the one or more tangible storage medium forexecution by at least one of the one or more processors via at least oneof the one or more memories, wherein the computer system is capable ofperforming a method. The computer system may include determining a setof data based on a description of events, wherein the set of datacomprises a plurality of data for which change capture is possible. Thecomputer system may also include selecting at least one item of datafrom within the determined set of data, wherein the at least one item ofdata requires change capture to be performed. Additionally, the computersystem may include identifying at least one published event based on theat least one selected item of data, wherein the at least one publishedevent is produced by the event publishing system. The computer systemmay include instructing the event publishing system to deliver the atleast one identified published event to the change capture system.Furthermore, the computer system may include receiving, by the changecapture system, the at least one identified published event. Thecomputer system may also include processing the at least one publishedevent received by the change capture system.

According to yet another embodiment, a computer program product forimplementing a change capture system using an event publishing system asa database recovery log is provided. The computer program product mayinclude one or more computer-readable tangible storage medium andprogram instructions stored on at least one of the one or more tangiblestorage medium, the program instructions executable by a processor. Thecomputer program product may include program instructions to determine aset of data based on a description of events, wherein the set of datacomprises a plurality of data for which change capture is possible. Thecomputer program product may also include program instructions to selectat least one item of data from within the determined set of data,wherein the at least one item of data requires change capture to beperformed. Additionally, the computer program product may includeprogram instructions to identify at least one published event based onthe at least one selected item of data, wherein the at least onepublished event is produced by the event publishing system. The computerprogram product may include program instructions to instruct the eventpublishing system to deliver the at least one identified published eventto the change capture system. Furthermore, the computer program productmay include program instructions to receive, by the change capturesystem, the at least one identified published event. The computerprogram product may include program instructions to process the at leastone published event received by the change capture system.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

These and other objects, features and advantages of the presentinvention will become apparent from the following detailed descriptionof illustrative embodiments thereof, which is to be read in connectionwith the accompanying drawings. The various features of the drawings arenot to scale as the illustrations are for clarity in facilitating oneskilled in the art in understanding the invention in conjunction withthe detailed description.

FIG. 1 illustrates a networked computer environment according to oneembodiment.

FIG. 2 is an operational flow chart illustrating the steps carried outby a program to use published events to perform change capture.

FIG. 3 is an example of a change capture system that implements an eventpublishing system.

FIG. 4 is a block diagram of internal and external components ofcomputers and servers depicted in FIG. 1 according to at least oneembodiment.

DETAILED DESCRIPTION

Detailed embodiments of the claimed structures and methods are disclosedherein; however, it can be understood that the disclosed embodiments aremerely illustrative of the claimed structures and methods that may beembodied in various forms. This invention may, however, be embodied inmany different forms and should not be construed as limited to theexemplary embodiments set forth herein. Rather, these exemplaryembodiments are provided so that this disclosure will be thorough andcomplete and will fully convey the scope of this invention to thoseskilled in the art. In the description, details of well-known featuresand techniques may be omitted to avoid unnecessarily obscuring thepresented embodiments.

Embodiments of the present invention relate to the field of computing,and more particularly to change data capture. The following describedexemplary embodiments provide a system, method, and program product to,among other things, implement a change data capture system using anevents publishing system as a database recovery log.

As previously described, change capture technology utilizes the databaserecovery log from the source database to determine the changes thatoccur in the database. Additionally, the database recovery log may beused to analyze the changes made to the database. However, such use ofthe recovery log may have impact on both the resources and theadministration associated with the source database and the system onwhich the database resides. Change capture solutions may encompass avariety of use cases that may include homogeneous replication,heterogeneous replication, and event publishing. Many consumers of largechange capture systems may require support for more than one use casewith the same source data objects. However, such a multi-use model mayincrease overhead on the source system as multiple cursor positions inthe database recovery log need to be maintained. Furthermore, amulti-use model may result in multiple physical log readers. A logreader is a program that monitors the database for transactionalchanges. Upon detecting a database change, the log reader sends thechange information to a distribution database. Even in a situation wherethe same source capture system is implemented for all use cases, thesystem may require multiple log readers since there may still beexcessive overhead as log positioning can differ by use case.

Currently, systems, such as a log shipping system, may be used to reducethe number of physical log readers. A log shipping system sendstransactional logs from one database to another on a constant basis maybe. However, such a technique may not be available for all databasetechnologies and may incur additional overhead of their own. Therefore,it may be advantageous, among other things, to implement a changecapture system that utilizes the information produced by the eventspublishing system rather than the database recovery log in order toreduce the impact on and lessen overhead of the source database and thesystem on which the database resides.

According to at least one implementation of the present embodiment, asingle physical log reader may be used that emits all changes to apublished business events log (e.g. a replication log). Such a use case,referred to as an event publishing system, may act as a filtered logextender, which may isolate the selected subset of data change eventsinto a second replication log stream. Once established, homogeneous andheterogeneous capture engines may capture information from a databasewith less combined overhead. Therefore, multiple cursor positions may bemaintained in an optimized, filtered replication log stream moreefficiently than may be done in the original database recovery log,which may not have been designed for such real-time multi-user access.As such, the selected subset of data changes may be the aggregation ofall data requirements for the downstream use-cases. Pruning of thereplication log may occur as the respective use-cases offload andpersist those transactions in target database management.

Additionally, the change data capture system may enhance log readerfunctionality by using a log stream of published business events as analternate log source rather than using the database recovery log. Thepresent embodiment may subscribe to events being directly published by asource system. Utilizing the context available for that publication, thechange data capture system may determine the type of source databasechanges that may be inferred from the stream of published events. Assuch, according to at least one implementation, a user may select whichchanges may be logged. Therefore, the change data capture system mayoperate by recording the user selected changes as if the change capturesystem were capturing those changes directly from the database recoverylog.

In some cases, the published business events in the stream maycorrespond to the individual changes in the source database, such asinserting, updating, or deleting a row of data. In other instances, theevents may correspond to business events involving a set of changes tothe individual rows potentially across multiple tables. When the eventscorrespond to business events, business-specific logic may be requiredto determine the corresponding individual changes. Often, change capturemay acquire other information about the context of the data change. Forexample, a timestamp indicating when the change occurred and informationabout the business user who made the change may be captured by thesystem.

The present embodiment may minimize the impact on the source system aswell as deliver events to an additional subscriber for very little, ifany, additional cost for the source system.

The present invention may be a system, a method, and/or a computerprogram product. The computer program product may include a computerreadable storage medium (or media) having computer readable programinstructions thereon for causing a processor to carry out aspects of thepresent invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, or either source code or object code written in anycombination of one or more programming languages, including an objectoriented programming language such as Smalltalk, C++ or the like, andconventional procedural programming languages, such as the “C”programming language or similar programming languages. The computerreadable program instructions may execute entirely on the user'scomputer, partly on the user's computer, as a stand-alone softwarepackage, partly on the user's computer and partly on a remote computeror entirely on the remote computer or server. In the latter scenario,the remote computer may be connected to the user's computer through anytype of network, including a local area network (LAN) or a wide areanetwork (WAN), or the connection may be made to an external computer(for example, through the Internet using an Internet Service Provider).In some embodiments, electronic circuitry including, for example,programmable logic circuitry, field-programmable gate arrays (FPGA), orprogrammable logic arrays (PLA) may execute the computer readableprogram instructions by utilizing state information of the computerreadable program instructions to personalize the electronic circuitry,in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the block may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

The following described exemplary embodiments provide a system, methodand program product to implement a change data capture system using anevents publishing system as a database recovery log.

According to one implementation, using the database description ofevents, the change capture system may determine the set of tables fromwhich change data may be provided. Among this set of tables, a user maybe able to select which tables the change data capture system maysubscribe. Then, for each selected table, the change data capture systemmay subscribe to the relevant set of events. Capturing changes for agiven table may involve subscribing to more than one set of events.Similarly, a single set of events may provide change capture for morethan one source table. Once the change capture system has subscribed toa set of events, the change capture system may receive and persistevents published by the events publishing system. A change extractorcomponent may consume these events in the same fashion that may be donefor a database recovery log. The change extractor may remove events fromthe persisted store of events using the same algorithms that mayconventionally be used to provide log dependency information to thesource database.

Referring now to FIG. 1, an exemplary networked computer environment 100in accordance with one embodiment is depicted. The networked computerenvironment 100 may include a computer 102 with a processor 104 and adata storage device 106 that is enabled to run a Change Capture Program108A. The networked computer environment 100 may also include a server112 that is enabled to run a Change Capture Program 108B and acommunication network 110. The networked computer environment 100 mayinclude a plurality of computers 102 and servers 112, only one of whichis shown for illustrative brevity. According at least oneimplementation, the present embodiment may also include a database 114,which may be running on server 112. The communication network mayinclude various types of communication networks, such as a wide areanetwork (WAN), local area network (LAN), a telecommunication network, awireless network, a public switched network and/or a satellite network.It may be appreciated that FIG. 1 provides only an illustration of oneimplementation and does not imply any limitations with regard to theenvironments in which different embodiments may be implemented. Manymodifications to the depicted environments may be made based on designand implementation requirements.

The client computer 102 may communicate with server computer 112 via thecommunications network 110. The communications network 110 may includeconnections, such as wire, wireless communication links, or fiber opticcables. As will be discussed with reference to FIG. 4, server computer112 may include internal components 800 a and external components 900 a,respectively and client computer 102 may include internal components 800b and external components 900 b, respectively. Client computer 102 maybe, for example, a mobile device, a telephone, a personal digitalassistant, a netbook, a laptop computer, a tablet computer, a desktopcomputer, or any type of computing device capable of running a programand accessing a network.

According to the present embodiment, a program, such as a Change CaptureProgram 108A and 108B may run on the client computer 102 or on theserver computer 112. The Change Capture Program 108A, 108B may implementchange data capture by using an events publishing system as a databaserecovery log. The Change Capture method is explained in further detailbelow with respect to FIG. 2.

FIG. 2, an operational flowchart 200 illustrating the steps carried outby a program to use an events publishing system as a database recoverylog to perform change capture in accordance with one embodiment isdepicted. At 202, the Change Capture Program 108A, 108B (FIG. 1) maydetermine a set of data that change capture may be possible for based onthe information retained within the events publishing system. An eventpublishing system may include a description of events, which consists ofmetadata that provides information regarding the event publishing systemand events published by the event publishing system. Without theinformation contained in the description of events, an item produced bythe event publishing system may not be consumed since there is noindication of what that published event represents. Therefore, based onthe description of events, the present embodiment may determine a set ofdata, which may include the tables and columns within the tables, fromwhich changes may be extracted. For example, an events publishing systemmay publish events from a source database that retains customer records,such as customer name, customer address, products owned by the customer,and customer email. The information contained within the published eventmay originate from several different tables. By analyzing thedescription of events within the event publishing system, the ChangeCapture Program 108A, 108B (FIG. 1) may be able to determine the tablesand columns within tables from which the information in the publishedevent originated.

Next at 204, a user may be prompted by the Change Capture Program 108A,108B (FIG. 1) to select a subset of data (at least one item of datawithin the previously determined set of data) on which to perform changecapture. Once the Change Capture Program 108A, 108B (FIG. 1) determinesa set of data from which change capture is possible (as previouslydescribed in step 202), the user may select from the set of data whichdata the user would like change capture performed. For example, theChange Capture Program 108A, 108B (FIG. 1) may determine in step 202that change capture is possible for customer names, customer addresses,products owned by the customers, and customer emails based on the set ofdata. However, the user may only be interested in the tables containinginformation relating to customer addresses and customer emails.Therefore, the user may select customer addresses and customer emails asthe data on which the Change Capture Program 108A, 108B (FIG. 1) mayperform change capture. Selection of the data from the set of data maybe achieved through a graphical user interface (GUI), such as apull-down menu within a user interface of the Change Capture Program108A, 108B (FIG. 1).

Then at 206, the Change Capture Program 108A, 108B (FIG. 1) may identifywhich events to subscribe to based on the user selected data. For eachitem of data that the user selects (previously in step 204), the presentembodiment may be able to identify which events published by the eventpublishing system should be subscribed to in order to capture the datathe user desires. An event publishing system may produce a number ofevents that may be separated into different categories, such as personevents or product events. A person event may be an event that isgenerated by the event publishing system when information about thecustomer was changed in the source database. Similarly, a product eventmay be an event generated by the event publishing system wheninformation about a product was changed or a regulatory change was inputinto the source database. When an event that includes data the user maybe interested in is published by the event publishing system, the ChangeCapture Program 108A, 108B (FIG. 1) may identify that that type of eventshould be subscribed to so as to capture the data change. For example,the user may have selected customer addresses and customer emails as thedata in which the user is interested. Since a change in customeraddresses and customer emails may be considered a person event, theChange Capture Program 108A, 108B (FIG. 1) may identify all personevents should be subscribed to in order to effectively capture allchanges in which the user is interested.

Following next at 208, the Change Capture Program 108A, 108B (FIG. 1)may instruct the event publishing system to deliver (i.e. subscribe) tothe identified events based on the user selected data. Once the ChangeCapture Program 108A, 108B (FIG. 1) identifies which events produced bythe event publishing system should be subscribed to in order for theChange Capture Program 108A, 108B (FIG. 1) to capture all of the desireduser selected data, the event publishing system may be instructed todeliver (i.e. subscribe) the identified published events to the ChangeCapture Program 108A, 108B (FIG. 1). Subscribing to an identified eventmay mean that when an identified event occurs in the source database,the event publishing system may deliver information about the particularevent to the Change Capture Program 108A, 108B (FIG. 1). For example, ifthe present embodiment identifies in step 206 that all person eventsshould be subscribed to, then the present embodiment may subscribe toall person events so that the event publishing system sends informationto the present embodiment whenever a change to person data occurs. Theinformation sent by the event publishing system to the Change CaptureProgram 108A, 108B (FIG. 1) may be in the form of a published event.

Next at 210 within the Change Capture Program 108A, 108B (FIG. 1), allpublished events that have been subscribed to may be received. Wheneverthe event publishing system publishes an event of which the ChangeCapture Program 108A, 108B (FIG. 1) may have previously subscribed, theChange Capture Program 108A, 108B (FIG. 1) may receive the informationabout that published event. The received events by the Change CaptureProgram 108A, 108B (FIG. 1) may be placed in a repository, such as thedatabase 114 (FIG. 1). A repository may be a location where publishedevents are persistently stored.

Next at 212, the Change Capture Program 108A, 108B (FIG. 1) may processthe published events. Once the Change Capture Program 108A, 108B(FIG. 1) receives a published event and places it in the repository, thepublished event may be extracted from the repository using a set ofalgorithms similar to the set of algorithms conventionally used toprovide log dependency information to a source database. The ChangeCapture Program 108A, 108B (FIG. 1) may analyze the extractedinformation contained in the published event and determine which itemsof data contained within the published event may be relevant to the userselected data. The Change Capture Program 108A, 108B (FIG. 1) may beable to determine which user selected data may have changed and mayrecord changed user selected data. For example, when the user selecteddata is customer addresses, the Change Capture Program 108A, 108B(FIG. 1) may record table level data changes for each change in arepository in the user selected data that the Change Capture Program108A, 108B (FIG. 1) may receive through a published event. However, apublished event received by the Change Capture Program 108A, 108B(FIG. 1) may not contain any changed data relevant to the user selecteddata. For example, the Change Capture Program 108A, 108B (FIG. 1) mayreceive a person event that contains data relevant to customer phonenumber and customer email address. Of the information contained withinthe published event, the user selected data may only be the customeremail address. However, the published event only contains changed datafor the customer phone number even though the published event alsocontains unchanged data relating to the customer email address. As such,the Change Capture Program 108A, 108B (FIG. 1) may recognize that thepublished event does not contain any changed user selected data and maydisregard the published event.

Then at 214, it may be determined whether the method may terminate.According to one implementation, the method may terminate based onvarious circumstances, such as user intervention, the amount of elapsedtime, system performance, etc. If it is determined that the methodshould terminate, then the method may end. However, if at 214, it isdetermined that the method should not terminate, then the method maycontinue back to step 210 to receive the published events from the eventpublishing system.

It may be appreciated that FIG. 2 provides only an illustration of oneimplementation and does not imply any limitations with regard to howdifferent embodiments may be implemented. Many modifications to thedepicted environments may be made based on design and implementationrequirements. For example, as previously described, the presentembodiment may be implemented in hardware via a graphics display adapterto apply to either a subset or complete screen coverage and may be madesoftware selectable as needed.

Referring now to FIG. 3, an example 300 of change capture systeminterpreting published events similar to a database recovery log inaccordance with one embodiment is depicted. According to oneimplementation of the present embodiment, the change capture system 302may analyze the description of events 304 in order to determine a set ofdata that change capture may be performed upon. After a user selectsdata from the set of data on which to perform change capture (step 204(FIG. 2)) previously described) and the present embodiment identifiesevents on which to subscribe (step 206 (FIG. 2)) previously described),the present embodiment may subscribe to events published 310 by theevent publishing system 306 so whenever a specific change is made in asource database 308 the change capture system may receive a publishedevent 310 that may contain information relating to the user selecteddata. After subscribing to the identified published events 310, thechange capture system 302 may receive the published events 310 and storethose published events 310 as persisted events 312 within the changecapture system 302. Thereafter, the change capture system 302 mayconsume the persisted events 312. The consumption of the events withinthe change capture system 302 starts by extracting the changes 314 fromthe persisted events 312 stored within the change capture system 302.Then, the change capture system 302 may record the table level changes.However, the change capture system 302 may insert the extracted changes314 into a conventional change stream 316 to be processed by the clientcomputer 102 (FIG. 1) or client server 112 (FIG. 1).

FIG. 4 is a block diagram 400 of internal and external components ofcomputers depicted in FIG. 1 in accordance with an illustrativeembodiment of the present invention. It should be appreciated that FIG.4 provides only an illustration of one implementation and does not implyany limitations with regard to the environments in which differentembodiments may be implemented. Many modifications to the depictedenvironments may be made based on design and implementationrequirements.

Data processing system 800, 900 is representative of any electronicdevice capable of executing machine-readable program instructions. Dataprocessing system 800, 900 may be representative of a smart phone, acomputer system, PDA, or other electronic devices. Examples of computingsystems, environments, and/or configurations that may represented bydata processing system 800, 900 include, but are not limited to,personal computer systems, server computer systems, thin clients, thickclients, hand-held or laptop devices, multiprocessor systems,microprocessor-based systems, network PCs, minicomputer systems, anddistributed cloud computing environments that include any of the abovesystems or devices.

User client computer 102 (FIG. 1), and network server 112 (FIG. 1) mayinclude respective sets of internal components 800 a, b and externalcomponents 900 a, b illustrated in FIG. 4. Each of the sets of internalcomponents 800 a, b includes one or more processors 820, one or morecomputer-readable RAMs 822 and one or more computer-readable ROMs 824 onone or more buses 826, and one or more operating systems 828 and one ormore computer-readable tangible storage devices 830. The one or moreoperating systems 828 and the Change Capture Program 108A (FIG. 1) inclient computer 102 (FIG. 1) and Change Capture Program 108B (FIG. 1) innetwork server computer 112 (FIG. 1) are stored on one or more of therespective computer-readable tangible storage devices 830 for executionby one or more of the respective processors 820 via one or more of therespective RAMs 822 (which typically include cache memory). In theembodiment illustrated in FIG. 4, each of the computer-readable tangiblestorage devices 830 is a magnetic disk storage device of an internalhard drive. Alternatively, each of the computer-readable tangiblestorage devices 830 is a semiconductor storage device such as ROM 824,EPROM, flash memory or any other computer-readable tangible storagedevice that can store a computer program and digital information.

Each set of internal components 800 a, b, also includes a R/W drive orinterface 832 to read from and write to one or more portablecomputer-readable tangible storage devices 936 such as a CD-ROM, DVD,memory stick, magnetic tape, magnetic disk, optical disk orsemiconductor storage device. A software program, such as Change CaptureProgram 108A (FIG. 1), 108B (FIG. 1) and the database 114 (FIG. 1), canbe stored on one or more of the respective portable computer-readabletangible storage devices 936, read via the respective R/W drive orinterface 832 and loaded into the respective hard drive 830.

Each set of internal components 800 a, b also includes network adaptersor interfaces 836 such as a TCP/IP adapter cards, wireless Wi-Fiinterface cards, or 3G or 4G wireless interface cards or other wired orwireless communication links. The Change Capture Program 108A (FIG. 1)in client computer 102 (FIG. 1) and Change Capture Program 108B (FIG. 1)in network server 112 (FIG. 1) can be downloaded to client computer 102(FIG. 1) from an external computer via a network (for example, theInternet, a local area network or other, wide area network) andrespective network adapters or interfaces 836. From the network adaptersor interfaces 836, the Change Capture Program 108A (FIG. 1) in clientcomputer 102 (FIG. 1) and the Change Capture Program 108B (FIG. 1) innetwork server computer 112 (FIG. 1) are loaded into the respective harddrive 830. The network may comprise copper wires, optical fibers,wireless transmission, routers, firewalls, switches, gateway computersand/or edge servers.

Each of the sets of external components 900 a, b can include a computerdisplay monitor 920, a keyboard 930, and a computer mouse 934. Externalcomponents 900 a, b can also include touch screens, virtual keyboards,touch pads, pointing devices, and other human interface devices. Each ofthe sets of internal components 800 a, b also includes device drivers840 to interface to computer display monitor 920, keyboard 930 andcomputer mouse 934. The device drivers 840, R/W drive or interface 832and network adapter or interface 836 comprise hardware and software(stored in storage device 830 and/or ROM 824).

The descriptions of the various embodiments of the present inventionhave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to best explain theprinciples of the one or more embodiment, the practical application ortechnical improvement over technologies found in the marketplace, or toenable others of ordinary skill in the art to understand the embodimentsdisclosed herein.

What is claimed is:
 1. A method for implementing a change capture systemusing an event publishing system as a database recovery log, the methodcomprising: determining a set of data based on a description of events,wherein the set of data comprises a plurality of data for which changecapture is possible; selecting at least one item of data from within thedetermined set of data, wherein the at least one item of data requireschange capture to be performed; identifying at least one published eventbased on the at least one selected item of data, wherein the at leastone published event is produced by the event publishing system, andwherein the at least one published event is a person event where aplurality of information related to a customer is changed in a sourcedatabase; instructing the event publishing system to deliver the atleast one identified published event to the change capture system;receiving, by the change capture system, the at least one identifiedpublished event; extracting the at least one identified published eventfrom a persisted store, wherein the at least one identified publishedevent is extracted from the persisted store using an algorithm thatprovides log dependency information for a source database; analyzing aplurality of information contained within the at least one identifiedpublished event; identifying a change associated with the at least oneitem of selected data; and recording the identified change to the atleast one item of selected data to a repository.
 2. The method of claim1, wherein the recording of the identified change comprises recording aplurality of contextual information regarding the identified change tothe at least one item of selected data, wherein the plurality ofcontextual information comprises a timestamp of the identified change tothe at least one item of selected data and a plurality of customerinformation.
 3. The method of claim 1, wherein the selected at least oneitem of data is selected by a graphical user interface (GUI) comprisinga list of a plurality of table data and a plurality of column data. 4.The method of claim 1, wherein the determined set of data comprises aplurality of tables and a plurality of columns within the plurality oftables.
 5. The method of claim 1, wherein the identified change to theat least one item of selected data comprises at least one of aninsertion of a plurality of information to the source database; anupdate to a plurality of information in the source database; and adeletion of a plurality of information in the source database.